Disposable knife



FIG. 1 is a perspective view of my new design showing a disposable knife;

FIG. 2 is another perspective view of my new design showing a disposable knife;

FIG. 3 is a front elevation view of FIG. 1;

FIG. 4 is a rear elevation view of FIG. 1;

FIG. 5 is an enlarged elevation view of V in FIG. 1;

FIG. 6 is an enlarged cross section taken along VI-VI in FIG. 3; and,

FIG. 7 is an enlarged cross section taken along VII-VII in FIG. 3.

The short dash-long dash broken lines in FIGS. 1 and 5, designating the boundary of the enlarged view, form no part of the claimed design. 

CLAIM The ornamental design for a disposable knife, as shown and described. 